Reverberatory furnace



July 31, 1951 J. STR QMAN' 2,562,441

REVERBERATORY FURNACE Filed May 18, 1948 4 Sheets-Sheet l 2a I JQcAZQJWO/W July 31, 1951 I J. L. STROMAN 2,562,441

' REVERBERATORY FURNACE Filed May 18, 1948 4 Sheets-Sheet 2 July 31, :1951

J. STROMAN REVERBERATORY FURNACE Filed May 18 1948 4 Sheets-Sheet 5 f'wenivr I Jad/ LSZ?" July 31, 1951 Y J. L. STROMAN 2,562,441

REVERBERATORY FURNACE Filed May 18, 1948 4 Sheets-Sheet 4 Patented July 31, 1951 REVERBERATORY FURNACE Jack L. Stroman, Itasca, 111., assignor to The Petersen Oven Comp ration of Illinois any, Chicago, 111., a corpo- Application -May 18, 1948, Serial N 0. 27,800

1 Claim. (Cl. 253-33) The present invention relates to reverberatory smelting furnaces. More particularly, the invention is directed .to a novel furnace, preferably of the tiltable type, adapted for melting-all typesof ferrous and nonferrousmetals and alloys, even alloys of high temperature type for castinglbelow 3000 degrees F., as well .as various ceramic type materials. 1

An object of the present invention is the provision of such a furnace having a novel form of combustion andmelting chamber.

Another object of theinvention is .the provision of a furnace of this general class, in which there is no throat, such as is usually provided insuch furnaces.

smelting furnace, characterized by the provision of a chamber in the shape of a U, in which the bottom portion forms the combustion chamber and alsoserves to contain the moltenmaterial.

Another object is the provision of .such a furnace in which the flame, for melting the metal, or other material being processed, is directed verticallydownwardly .onto the material.

A further object is the-provision of a melting furnace in which the flame jets are so positioned with respect to the combustion chamber that the hottest part of the flame impinges .on the metal or other material being processed.

A still further object is the provision of a furnace having a chamber of such a shape that the flame is caused to impinge on the metal in the ing the lining of the furnace for removing unmelted metal therefrom.

A further object is the provision of a novel type of tilting furnace which can be tilted for pouring the molten metal out through the exhaust passage if such should be found desirable.

A still further object is the provision of a furnace having a chamber in the shape of a U and having removable arches, in which when the arches are removed, the combustion chamber and the firing and exhaust passages have one side .open and are readily accessible for relining, re-

pairing, or replacing firebrick.

'Other objects and advantages of this inven- A further object isthe provision of an improved otherwise secured together.

tion will be apparentfrom the following description, takenin connection with theacc'ompanying drawings, in which:

. Figurel is a perspective view of the metal melting furnace in a tilted position; Figure 2 is an enlarged view from the front of the furnace, as viewed in Figure ,1, but with the furnace in upright position;

Figure 3 is an end view, taken from the left of Figure 2; I

Figure 4 is aplan view on a reduced scale, show.- ing only the metal imeltingchamber with sup porting frame and appliances removed;

Figure 5 is a sectional view taken on line 5-5 ,of Figure 4;

Figure 6 is a sectional view on a reduced scale taken on line B-6 of Figure 4, but with the arch removed; and

Figure 7 is a side view-of. one of the sections making up the arch.

Referring now in detail to the drawings, the furnace of my invention includes a-supporting frame indicated generally at I 2, which isjmade up of .a number of structural members welded or The frame is made up of end members It positioned in spaced apart relation "and interconnected by other members,

such as l6. Ateach end of the frame 12 are cra- ,dle rollers 18, which arejournaled in brackets 20, secured tothe upper surfaces of the end-members I4 of the frame. The rollers is are arranged in 'pairs, the rollers of each pair being axially aligned and the pairs being positioned at the front and rear, respectively, of the frame. Each of the. rollers i8 is provided with alateral flange 22, the flanges of each pair being positioned onthe outer sides axially oftherollers.

Supported on .the frame l2, and particularly mounted in the cradle rollers i8, is the furnace proper, or melting chamber, indicated by the'numeral 24. The melting chamber 24 isof a novel shape andconstruction and is generally in the shape of a U. The chamber 24 includes a bottom rounded portion 26 and two vertical portions, or legs, 28 at the front and 30 at the rear. The chamber is made up of a metal shell 32 having a portion 34 conforming to the outer surface of the U, and side Wall portions 36, The shell is lined with firebrick -38 to the desired thickness, leaving a continuous channel or passage 40 having, segments in each of the legs 28' and 30 and a curved segment in the bottom portion 2-6. The channel comprising the bottom portion. 26 is, of course,

.roundedand is greater in depth than the width of which is turned against locking plate 52.

of the channel faces inwardly of the U, that is, the segment in the bottom portion opens upwardly, and the segments in the legs have their open sides facing toward each other.

A number of arch sections 4| (Figures 1 and '7) are secured across the open side of the channel 40 formed in the melting chamber. Figure 7 shows the construction of the arch sections; these sections are included in the subject matter of my co-pending application, Serial No. 708,682, filed November 8, 1946, but for convenience a brief description of them will be given here. Each section 4| includes a top member 42 having a horizontal plate 43 and an upstanding rib 44. Adjacent the ends of the member 42 are end plates 46, secured to and extending downwardly from the underside of the plate 43. Rein forcing plates 48 are provided for strengthening the end plates 46. One end plate 46 is provided with a threaded hole for receiving lockscrew 50, A plurality of fire brick 54 are positioned between the locking plate 52 and the end plate 46 at the opposite end of the arch section and held in place by the lockscrew 50. When the series. of

fire brick are thus located and locked in the section, they form, in effect, a monolithic mass of fire brick. The brick are of greater transverse dimensions than the plates 43 and 4B. The sections 4| are positioned across the open sides of the channel 40 formed in the melting chamber,

and are of appropriate length to reach from end to end across the chamber. The shell 32 of the chamber is provided with appropriate flanges,

such as 56, by means of which the sections 4| are secured in place. Figures 1 and illustrate 20 best advantage the positions of the sections The arch sections 4|, when in placeas above described-close the open sides of the channel 40 and close the melting chamber. The melting chamber thus includes a combustion chamber 58 at the bottom thereof and, as seen from Figure 5, has curved surfaces at the front and back, and a firing passage 60 and a combined exhaust and charging passage 62. The firing passage 60 and charging passage 62 are thus positioned ad jacent the front and rear marginal edge, re-

spectively, of the combustion chamber and are within the horizontal confines thereof. It will be observed that thefiring and charging passages extend vertically upwardly from the combustion chamber in keeping with the fact that the chamber proper is of U shape formation.

Adjacent the top of the firing passage 60 are burner blocks 64, one of which may be supported in place by a ledge 66, imbedded in'the fire brick 38, and the other one secured in place by resting on a ledge 61 on the firebrick of one of the arch sections 4|, the firebrick thereabove having been offset to form the ledge. The burner'blocks 64 form a restricted inlet 68 of minor depth at the upper end of the firing passage, butit will be noted that, except for the restricted inlet 68 the firing-passage is otherwise of uniform dimensions throughout its vertical extent. The combined charging and exhaust passage 62 is also of uniformtransverse dimensions throughout its vertical extent. As observed from Figures 1 and 4, the passages 60 and 62 are elongated, rectangular cross sectional dimensions with their long dimensions extending transversely across the furnace, or from end to end.

as having'its upper limit'adjacent the lower ends .the lower end of the leg 28, or at approximately the juncture between the combustion chamber 58 and the firing passage 60. The pouring spout I0 is formed by displacing outwardly a portion 12 of the shell 32 and securing side walls 14 thereto with fire brick. The spout is lined with firebrick for a portion of its extent, and completed with refractory material 16 which is molded in place over the firebrick, leaving an opening 18 communicating with the combustion chamber and opening out of the furnace. The outer extremity of the opening 18 is substantially at the level of the upper limit of the combustion chamber, or the juncture between the combustion chamber and the passages 66' and 62.

On each end of the furnace proper 24 is a bearing element 86 having an arcuate bearing surface 82. The bearing surface 82 is enclosed and strengthened by a metal plate 84. The end of the bearing member 80, adjacent the front of the furnace terminates a short distance above the bottom of the furnace, and the other end. which is adjacentthe rear, or exhaust passage 62, is carried upwardly to a position adjacent the upper end of the furnace, or charging passage. A chain, or other flexible means 86 has its ends secured to the bearing member 80, adjacent the ends of the latter by means of clamps, such as 88. Each chain is disposed on the bearing surface 82 of the respective bearing members, but is of greater length circumferentially than the bearing surface and depends below the bottom of the arcuate bearingsurface. The furnace proper 24 is Supported on the frame I2 by means of the bearing members resting in the cradle rollers 8.

Sprockets 96 are secured to a shaft 92 immediately below the respective arcuate bearing members. The shaft 92 is journaled in bearings, such as 94, spaced therealong and supported by the frame l2. Thesprockets are engaged by and in mesh with the respective chains 86.

At one end, of the frame I2 is a housing 96, for enclosing a drive motor and speed reduction means. The drive means may constitute an electric motor 98 and speed reducer I00 which are of conventional construction, interconnected by belt means I02. The gear reducer I00 includes a shaft IE4 with a sprocket I06 thereon. A chain I08 is trained over the sprocket I06 and over another sprocket IIO, secured on the shaft 92. The motor 98 is provided with the usual controls, including starting switches, limit switches, etc.

Positioned at the upper end of the passage 66 are a plurality of flame jets or burners H2, the

number of which may vary according to the amount of heat desired and material to be melted. The burners ||2 may be conventional mixerburners and are arranged for directing flames directly downwardly into the firing passage 60.

The burners are spaced along the long dimension of the firing passage and communicate with a fuel supply line I I4, having a suitable connection with asource of fuel by means of a flexible hose. The burners may be mounted in any convenient manner in desired position and are connected to a manifold H6. The manifold H6 is connected with the outlet of a blower I I8, which is operated by asuitable electric motor I20, or other means.

The blower and motor'ar'e mounted on a platform I22, welded or otherwise suitably secured to 'theadjacent bearing member 80. The blower and motor are thus carried by the furnace proper. A convenient shield 125 may be mounted adjacent the burners I ii! for shielding the flame.

A second pouring spout it may, if desired, be provided atthe rear of the furnace, as indicated in dot dash lines at the left of Figure 5, similar to the pouringspoutatthe front of the furnace.

Use and operation The furnace is charged with metalor other material to be melted through the combined exhaust and firing passage 62. The burnersli z are disposed for directing "flame downwardly'in the firing passage 60. The metal or material in falling through the charging passage 52 enters into the combustion chamber 58' and the flame on'leaving the burners projects down into the combustion space and is de'flected'by the bottom of the combustion chamber and across the cornbustion chamber and then upwardly through the exhaust passage. All of the heat from the flame is directed onto the incoming material through the exhaust passage. When the material begins to melt and form a molten bath on the bottom of the combustion chamber, the flame impinges amount of heat required for the particular material being melted. The burners H2 are distributed or spaced along the long transverse dimension of the firing passage 60 so that the heat fromthe flame is distributed evenly throughout the interior of the furnace. While the illustration herein shows two such burners, it will be understood, of course that the number of burners can be varied. Because of the vertical arrangement of the firing passage, and the positioning of the burners at the top thereof, the flame possesses the greatest amount of heat in approximately the vicinity of the material being melted.

A novel feature of the present invention is that the flame impinges downwardly and into the vicinity of the pouring spout l0, and in the customary use of the device the spout 10 remains open and a portion of the flame is deflected outwardly through the pouring spout; in this manner, the walls of the pouring spout are retained heated so that they do not chill the molten metal when the metal is poured.

The U shape chamber of the reverberatory furnace is entirely novel. The chamber includes vertically disposed firing and exhaust passages communicating with the combustion chamber at the bottom, and the passages being within the vertical projection of the horizontal confines of the combustion chamber. An advantage of this type of furnace will be found from the above general description, namely that all of the flame and heated gases are deflected from the firing passage across all of the combustion chamber and then out the combination exhaust and charging passage. None of the flame and heated gases can escape without first having come in contact with the material in the furnace. There are no throats or constrictions in the interior of the furnace.

By reason'o'f the fact that the arch sections d! can all be removed, the whole interior of the furnace can be made readily accessible for replacement, repair of fire brick, or for relining the furnace. Whenthe arch sections are removed, the channel segments forming the firing and exhaust passages and thecombustion chamber all have one side open and exposed so that workmen can easily gain access to the interior of the entire furnace.

The operation of the blower I H3, in connection with the flame jets or burners I I2, is believed to be readily apparent. blower, air is driven into the manifold HE and then into the burners. Thisair produces an inspirator effect, drawing gas from the line. H4 which is mixed with the air in the proper combustion proportions for the most efficient combustion of the fuel.

The furnace is readily adaptable to burning of other types of fuel besides gas, such as liquid, solid, solid pulverized fuel, or a combination of any of these.

The tilting operation of the furnace is brought about by means of the motor 98. The motor 98 is a reversible motor and is equipped with appropriate starting switches. Whenthe motor is turned on and rotated in a given direction, the drive is transmitted through the gear reducer Hit and through the chain I08 and sprocket III]. This rotates the shaft 92 which of course rotates the sprocket 99. The sprocket on rotating clockwise (Figure 3) tilts the furnace clockwise to the position illustrated in Figure 1 wherein the moltenmetal will discharge from the pouring spout H3. Rotation of the sprocket 9b in the opposite direction will tilt the furnace back to its normal upright position, illustrated in Figure 3, and on continued rotation, the furnace can be tilted in the opposite direction from that illustrated in Figure 1.

If a spout 1G is provided at the rear of the furnace, the metal can be poured therethrough nace can be tilted a further extent to a position wherein the exhaust passage 62 slopes downward'ly toward its normally upper end and the molten metal can be poured through the exhaust passage 62. For the latter purpose, the bearing member 8c is continued upwardly adjacent the exhaust passage a greater distance than on the opposite side so that the furnace can be tilted rearwardly a greater extent. It will be understood that the bearing surfaces 82 on the opposite ends of the furnace move on the cradle rollers l 8 and the furnace tilts on the axis of the arcs of the bearing surfaces.

Another advantage of the rearward tilting of the furnace is that the exhaust passage can be accessible to a workman for skimming off any slag accumulation on the molten bath, or for stirring or puddling or for general observation.

Another advantage of the construction is that the furnace can be tilted rearwardly so that metal which tends to cling to the brick work, above the level of the molten bath, can be removed by immersing it in the bath. The bath On actuation of the.

7 causes the clinging metal to melt and flow into the bath.

While I have herein shown and described a preferred embodiment of my invention, manifest- 1y it is capable of modification and rearrangement of parts without departing from the spirit and scope thereof. I do not, therefore, wish to be understood as limiting this invention to the precise form herein disclosed, except as I ma be so limited by the appended claim.

I claim as my invention:

A furnace of the character described, comprising, a refractory lined smelting chamber, said chamber being U-shape and having a bottom and upstanding legs, said bottom and legs having channel segments therein forming a continuous channel, the open sides of the channel segments in said legs facing each other and the open side of the channel segment in said bottom facing upwardly, the inner edges of said legs being disposed at an abrupt angle with respect to the'upper edge of said bottom, removable refractory arch sections secured across the chan- JACK L. STROMAN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 990,765 Nau i Apr. 25, 1911 1,924,200 Schufiler Aug. 29, 1933 1,970,186 Pontzen Aug. 14, 1934 2,300,141 Whitzel Oct. 2'7, 1942 2,436,124 Sklenar Feb. 17, 1948 2,455,531 Stroman Dec. 7, 1948 

